Interpreting Locative Expressions
A locative expression is an expression involving a locative prepositional phrase together with
whatever the phrase modifies. An example of a simple locative is: the tree in front of the house.
As part of my Ph.D., I developed a framework for interpreting locative expressions containing
the prepositions in front of and behind. These prepositions have different semantics in the
viewer-centred and intrinsic frames of reference (Vandeloise 1991). I defined a model of their semantics in each frame of reference. The basis of these models is a novel parameterized continuum function that
creates a 3-D spatial template. In the intrinsic frame of reference the origin used by the continuum
function is assumed to be known a priori and object occlusion does not impact on the applicability rating
of a point in the spatial template. In the viewer-centred frame the location of the spatial template's
origin is dependent on the location of the user relative to the landmark at the time of the utterance and
object occlusion is integrated into the model. Where there is an ambiguity with respect to the intended
frame of reference, I defined an algorithm for merging the spatial templates from the competing frames
of reference, based on psycholinguistic observations in (Carlson-Radvansky and Logan 1997).
A book chapter describing the model, entitled kelleher/vangenabith:06 provides more information on this model and kelleher/costello:05 describes an experiment that was run to test the model.